FEMORAL HERNIA. 



1197 



femoral sheath is closely adherent to the contained vessels about an inch below 

 the saphenous opening, being blended with the areolar sheath of the vessels, 

 but opposite Poupart's ligament it is much larger than is required to contain them ; 

 hence the funnel-shaped form which it presents. The outer border of the sheath 

 is perforated by the genito-crural nerve. Its inner border is pierced by the internal 

 saphenous vein and numerous lymphatic vessels. In front it is covered by the 

 iliac portion of the fascia lata ; and behind it is the pubic portion of the same 

 fascia. 



If the anterior wall of the sheath is removed, the femoral artery and vein are 

 seen lyin side by side, a thin septum separating the two vessels, while another 

 septum may be seen lying just internal to the vein, and cutting off a small space 

 between the vein and the inner wall of the sheath. The septa are stretched between 

 the anterior and posterior walls of the sheath, so that each vessel is enclosed in 

 a separate compartment. The interval left between the vein and the inner 

 wall of the sheath is not filled up by any structure, excepting a little loose 

 areolar tissue, a few lymphatic vessels, and occasionally by a small lymphatic 



FIG. 766. Hernia. The relations of the femoral and internal abdominal rings, seen from within the abdo- 

 men. Right side. 



gland : this is the femoral or crural canal, through which the intestine descends in 

 femoral hernia. 



Deep Crural Arch. Passing across the front of the crural sheath on the 

 abdominal side of Poupart's ligament, and closely connected with it, is a thickened 

 band of fibres called the deep crural arch. It is apparently a thickening of the 

 fascia transversalis, joining externally to the centre of Poupart's ligament, and 

 arching across the front of the crural sheath, to be inserted by a broad attachment 

 into the pectineal line behind the conjoined tendon. In some subjects this 

 structure is not very prominently marked, and not unfrequently it is altogether 

 wanting. 



The crural canal is the narrow interval between the femoral vein and the inner 

 wall of the crural sheath. It exists as a distinct canal only when the sheath has 

 been separated from the vein by dissection or by the pressure of a hernia or tumor. 

 Its length is from a quarter to half an inch, and it extends from Gimbernat's liga- 

 ment to the upper part of the saphenous opening. 



Its anterior wall is very narrow, and formed by a continuation downward of 

 the fascia transversalis, under Poupart's ligament, covered by the falciform pro- 

 cess of the fascia lata. 



